From: Al Viro <[email protected]>
To: Andy Lutomirski <[email protected]>
Cc: Christoph Hellwig <[email protected]>,
Andrew Morton <[email protected]>,
Jens Axboe <[email protected]>, Arnd Bergmann <[email protected]>,
David Howells <[email protected]>,
[email protected], [email protected],
[email protected], [email protected],
[email protected], [email protected],
[email protected], [email protected],
[email protected], [email protected],
[email protected], [email protected],
[email protected], [email protected],
[email protected], [email protected],
[email protected], [email protected]
Subject: Re: [PATCH 1/9] kernel: add a PF_FORCE_COMPAT flag
Date: Sat, 19 Sep 2020 23:41:22 +0100 [thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
On Sat, Sep 19, 2020 at 03:23:54PM -0700, Andy Lutomirski wrote:
>
> > On Sep 19, 2020, at 3:09 PM, Al Viro <[email protected]> wrote:
> >
> > On Fri, Sep 18, 2020 at 05:16:15PM +0200, Christoph Hellwig wrote:
> >>> On Fri, Sep 18, 2020 at 02:58:22PM +0100, Al Viro wrote:
> >>> Said that, why not provide a variant that would take an explicit
> >>> "is it compat" argument and use it there? And have the normal
> >>> one pass in_compat_syscall() to that...
> >>
> >> That would help to not introduce a regression with this series yes.
> >> But it wouldn't fix existing bugs when io_uring is used to access
> >> read or write methods that use in_compat_syscall(). One example that
> >> I recently ran into is drivers/scsi/sg.c.
> >
> > So screw such read/write methods - don't use them with io_uring.
> > That, BTW, is one of the reasons I'm sceptical about burying the
> > decisions deep into the callchain - we don't _want_ different
> > data layouts on read/write depending upon the 32bit vs. 64bit
> > caller, let alone the pointer-chasing garbage that is /dev/sg.
>
> Well, we could remove in_compat_syscall(), etc and instead have an implicit parameter in DEFINE_SYSCALL. Then everything would have to be explicit. This would probably be a win, although it could be quite a bit of work.
It would not be a win - most of the syscalls don't give a damn
about 32bit vs. 64bit...
next prev parent reply other threads:[~2020-09-19 22:41 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-18 12:45 let import_iovec deal with compat_iovecs as well Christoph Hellwig
2020-09-18 12:45 ` [PATCH 1/9] kernel: add a PF_FORCE_COMPAT flag Christoph Hellwig
2020-09-18 13:40 ` Al Viro
2020-09-18 13:44 ` Christoph Hellwig
2020-09-18 13:58 ` Al Viro
2020-09-18 15:16 ` Christoph Hellwig
2020-09-19 16:21 ` Andy Lutomirski
2020-09-19 21:16 ` Arnd Bergmann
2020-09-19 21:52 ` Finn Thain
2020-09-19 22:22 ` Andy Lutomirski
2020-09-21 16:10 ` Pavel Begunkov
2020-09-21 16:13 ` Pavel Begunkov
2020-09-21 23:51 ` Andy Lutomirski
2020-09-22 0:22 ` Pavel Begunkov
2020-09-22 0:58 ` Andy Lutomirski
2020-09-22 6:30 ` Pavel Begunkov
2020-09-22 7:23 ` Arnd Bergmann
2020-09-22 7:57 ` Pavel Begunkov
2020-09-22 9:01 ` Arnd Bergmann
2020-09-22 16:20 ` Andy Lutomirski
2020-09-23 8:01 ` Pavel Begunkov
2020-09-23 13:22 ` Al Viro
2020-09-19 22:09 ` Al Viro
2020-09-19 22:23 ` Andy Lutomirski
2020-09-19 22:41 ` Al Viro [this message]
2020-09-19 22:53 ` Andy Lutomirski
2020-09-19 23:24 ` Al Viro
2020-09-20 0:14 ` Andy Lutomirski
2020-09-20 2:57 ` Al Viro
2020-09-20 16:59 ` Andy Lutomirski
2020-09-20 18:12 ` Al Viro
2020-09-20 13:55 ` Arnd Bergmann
2020-09-20 15:02 ` Al Viro
2020-09-19 14:53 ` David Laight
2020-09-18 13:59 ` Arnd Bergmann
2020-09-20 15:15 ` Matthew Wilcox
2020-09-20 15:55 ` William Kucharski
2020-09-21 16:20 ` Pavel Begunkov
2020-09-20 16:00 ` Arnd Bergmann
2020-09-20 18:07 ` Al Viro
2020-09-20 18:41 ` Al Viro
2020-09-20 19:01 ` Matthew Wilcox
2020-09-20 19:10 ` Al Viro
2020-09-20 19:22 ` Matthew Wilcox
2020-09-20 19:28 ` Andy Lutomirski
2020-09-20 20:49 ` Arnd Bergmann
2020-09-20 21:13 ` David Laight
2020-09-21 16:31 ` Pavel Begunkov
2020-09-20 21:42 ` Al Viro
2020-09-21 16:26 ` Pavel Begunkov
2020-09-20 19:14 ` Andy Lutomirski
2020-09-21 4:28 ` Christoph Hellwig
2020-09-18 12:45 ` [PATCH 2/9] compat.h: fix a spelling error in <linux/compat.h> Christoph Hellwig
2020-09-18 13:37 ` Johannes Thumshirn
2020-09-18 12:45 ` [PATCH 3/9] fs: explicitly check for CHECK_IOVEC_ONLY in rw_copy_check_uvector Christoph Hellwig
2020-09-18 12:56 ` Matthew Wilcox
2020-09-18 13:39 ` Johannes Thumshirn
2020-09-18 12:45 ` [PATCH 4/9] fs: handle the compat case in import_iovec Christoph Hellwig
2020-09-18 12:45 ` [PATCH 5/9] fs: remove various compat readv/writev helpers Christoph Hellwig
2020-09-18 12:45 ` [PATCH 6/9] fs: remove the compat readv/writev syscalls Christoph Hellwig
2020-09-18 12:45 ` [PATCH 7/9] fs: remove compat_sys_vmsplice Christoph Hellwig
2020-09-18 12:45 ` [PATCH 8/9] mm: remove compat_process_vm_{readv,writev} Christoph Hellwig
2020-09-18 13:48 ` Arnd Bergmann
2020-09-18 12:45 ` [PATCH 9/9] security/keys: remove compat_keyctl_instantiate_key_iov Christoph Hellwig
2020-09-19 14:24 ` let import_iovec deal with compat_iovecs as well David Laight
2020-09-21 4:41 ` 'Christoph Hellwig'
2020-09-21 11:11 ` David Laight
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox